The global climate community is on high alert as El Niño has officially commenced. Meteorological experts are currently projecting a significant probability—exceeding 60%—that this naturally occurring phenomenon will intensify into a “very strong” or “super” El Niño as we move later into 2026.
While El Niño is a recurring part of Earth’s climate system, the transition from a standard event to a “super” event carries profound implications for the entire planet.
At its core, El Niño is characterized by an unusual warming of surface waters in the central and eastern Pacific Ocean near the equator. This localized change in ocean temperature acts as the first domino in a global cascade, triggering dramatic shifts in atmospheric circulation.
These shifts, known as teleconnections, can disrupt weather patterns thousands of miles away, translating high Pacific temperatures into a chaotic mix of severe floods, prolonged droughts, and intensified storm systems across different continents.
To better understand this complex chain of events, The Conversation Weekly podcast recently featured Ioana Colfescu, a distinguished expert in climate science and machine learning from the University of St Andrews and the University of Edinburgh. Colfescu provides a deep dive into the mechanics of El Niño, explaining how researchers utilise advanced data to predict what these shifts mean for the global population.
The history of El Niño stretches back centuries, long before modern satellite tracking. In the early 1600s, coastal fishermen in Peru and Ecuador were the first to document the anomaly.
Their livelihoods depended on the cold, nutrient-rich waters of the Pacific, which were typically flush with anchovies. However, they noticed that every few years, the ocean would turn uncharacteristically warm, causing the anchovy populations to vanish. Because these peak warming periods often coincided with the holiday season, they named the phenomenon “El Niño”—Spanish for “the little boy” or “the Christ child.”
In the centuries following those early observations, science has transformed our understanding of the event. We now recognise this warming as a critical phase of a natural cycle known as the El Niño-Southern Oscillation (ENSO).
Modern scientists are constantly refining their models to predict not just when the next El Niño will arrive, but how severe its global footprint will be.
According to Colfescu, current indicators suggest this upcoming El Niño shares a similar trajectory and signature with previous “super” El Niños. However, she notes a crucial distinction: while the “temperature index” may confirm a massive event in terms of raw heat, that doesn’t always provide a perfect blueprint for its physical impact. “While we know it’s gonna be a big event in terms of temperature,” Colfescu explains, “this temperature index is not yet defined as a big event in terms of impact.”
Looking back at the 2023-24 El Niño provides a clear example of this complexity. That event ranked among the top five strongest ever recorded and contributed significantly to 2024 becoming the hottest year in history.
It fueled devastating floods in regions like Brazil, yet some other predicted weather disasters failed to materialize. Colfescu points out that El Niño’s impacts are often “nuanced,” as the atmosphere’s response can vary wildly between the tropics and regions further toward the poles.
Ultimately, the most concerning factor in modern El Niños is the influence of human-induced climate change. Colfescu warns that whatever severe weather occurs will likely be amplified. Because the oceans have already absorbed massive amounts of heat due to global warming, today’s El Niño is essentially “overlapped” on an already record-warm baseline, making the potential for “super” status and extreme weather even more precarious. (The Conversation)
